Electrochemical and in situ X-ray absorption spectroscopy (XAS) measurements of various MnO2-coated carbon materials (MnO2/acid-functionalized carbon nanotubes (C-CNT), MnO2/reduced graphene oxide (RGO), and MnO2/RGO-Au electrodes) were conducted to evaluate the supercapacitive performances and electronic structures. MnO2 was deposited on the surface of C-CNT, RGO, and RGO-Au via a spontaneous ...

This work presented a novel core-shell MnO2@m-SiO2 for catalyzing the removal of dyes from wastewater. MnO2 nanorods were sequentially coated with polydopamine (PDA) and polyethyleneimine (PEI) forming MnO2@PDA-PEI. By taking advantage of the positively charged amine groups, MnO2@PDA-PEI was further silicificated, forming MnO2@PDA-PEI-SiO2. After calcination, the composite MnO2@m-SiO2 was final...

Glyphosate, one of the organophosphate herbicides, has been widely used in the word. The removal of glyphosate was comparatively investigated by MnO2 oxidation, electrochemical oxidation, and electrochemically assisted MnO2 oxidation (electro-MnO2) processes. The effects of MnO2 dosage, current density, and solution pH on glyphosate removal and Mn release were examined. The results indicated th...

composite electrodes of polyaniline/mno2-multi walled carbon nanotube (pani/mno2-mwcnt), mno2-mwcnt nanocomposites and mwcnt was produced by the in situ direct coating approach. the supercapacitor performance of the nanocomposites was studied by fourier transform infrared (ft-ir) spectroscopy and scanning electron microscopy (sem). the electrochemical properties of electrodes were also investig...

A novel γ-MnO2 catalyst obtained by selective removal and other traditional MnO2 catalysts (α-, β-, δ-MnO2) were studied for their catalytic performance in toluene combustion. The new γ-MnO2 catalyst showed the best catalytic activity owing to its three-dimensional macroporous and mesoporous morphology and the γ-MnO2-like structure.

The nanocomposite materials of poly(3,4-ethylenedioxythiophene)/graphene oxide (PEDOT/GO), poly(3,4-ethylenedioxythiophene)/MnO2 (PEDOT/MnO2), and poly(3, 4-ethylenedioxythiophene)/graphene oxide/MnO2 (PEDOT/GO/MnO2) were successfully prepared by facile and template-free solution method. The structure and morphology of nanonanocomposites were characterized by Fourier transform infrared spectros...

The novel carbon (C)/MnO2 double-walled nanotube arrays (DNTAs) are designed and fabricated via template-assisted electrodeposition. The unique DNTA architectures of C/MnO2 composites with high weight fraction of MnO2 allow high electrode utilization ratio and facilitate electron and ion transmission. In the half-cell test, the hybrid C/MnO2 DNTAs as electrodes show a large specific capacitance...

The oxidation of arsenite (As(III)) by manganese oxide is an important reaction in both the natural cycling of As and the development of remediation technology for lowering the concentration of dissolved As(III) in drinking water. This study used both a conventional stirred reaction apparatus and extended X-ray absorption fine structure (EXAFS) spectroscopy to investigate the reactions of As(II...

MnO2/carbon nanotube [CNT] nanocomposites with a CNT core/porous MnO2 sheath hierarchy architecture are synthesized by a simple hydrothermal treatment. X-ray diffraction and Raman spectroscopy analyses reveal that birnessite-type MnO2 is produced through the hydrothermal synthesis. Morphological characterization reveals that three-dimensional hierarchy architecture is built with a highly porous...

We have fabricated a thin film of multilayered MnO2 whose interlayer is occupied with hexadecylpyridinium (HDPy) cations, using a simple anodic approach. The resulting film can effectively sorb iodide anions from aqueous solutions, even in the presence of NaCl or Na2SO4. The maximum sorption capacity was estimated to be 256 mg/g-MnO2, whereas a layered MnO2 film intercalated with K(+) ions show...